Process for changing supply spools and finish wound cops on draw-twisting and draw-winding machines

ABSTRACT

When the supply spool is to be replaced, the thread is severed between the supply spool and delivery mechanism. Next, a fresh supply spool is put in place and the new thread connected to the thread still in the stretching mechanism. Thereafter, the thread is pulled from the rollers below the preliminary stretching zone and brought to the waste cone. After attachment at the waste cone, the machine is started at low speed until the thread connection comes to the waste cone. Thereafter, the machine is accelerated to production speed.

United States Patent Preysch 1 July4,1972

- [54] PROCESS FOR CHANGING SUPPLY SPOOLS AND FINISH WOUND COPS ON DRAW-TWISTING AND DRAW- WllNDING MACHINES [72] lnventor: Fritz Preysch, Winterthur, Switzerland [73] Assignee: Rieter Machine Works, Ltd., Winterthur,

Switzerland [22] Filed: June 16, 1970 [21] Appl. No.: 46,720

[52] U.S.Cl. ..57/l56,57/34 TT, 57134.5

[51] Int. Cl. ..D01h 9/02 [58] Field of Search ..57/34 R, 34 HS,34 TT,55.5, 57/157 R, 157 S, 157 TS, 34.5; 28/713; 264/210, 290

[56] References Citedv UNITED STATES PATENTS 2,747,359 5/1956 Keefe, Jr ..57/34 T'l" 2,976,671 3/1961 Steen ..57/l57 S Noordenbos ..57/55.5 Mansfield et al 3,277,641 10/1966 ODonahue et al.... ..57/157 3,283,489 11/1966 Bakker ..57/34 3,328,951 7/1967 Potts et al. ...57/55.5 X 3,400,194 9/1968 Boone et al. ..57/157 X Primary Examiner-Stanley N. Gilreath Assistant Examiner-Wemer H. Schroeder Attorney-Kenyon & Kenyon Reilly Carr & Chapin [5 7] ABSTRACT When the supply spool is to be replaced, the thread is severed between the supply spool and delivery mechanism, Next, a fresh supply spool is put in place and the new thread connected to the thread still in the stretching mechanism. Thereafter, the thread is pulled from the rollers below the preliminary stretching zone and brought to the waste cone. After attachment at the waste cone, the machine is started at low speed until the thread connection comes to the waste cone. Thereafter, the machine is accelerated to production speed.

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PROCESS FOR CHANGING SUPPLY SPOOLS AND FINISH WOULD COPS N DRAW-TWISTING AND DRAW-WINDING MACHINES This invention relates to a process for changing the supply spools and finish-wound cops on draw-twisting and drawwinding machines having a stretching zone.

In order to change the supply spools on a draw-twisting machine, it has been known to cut the thread being supplied at a point directly beyond the supply spool when the supply spool no longer has enough material to produce a complete cop. Thereafter, the used supply spool has been removed and replaced by a fresh supply spool. After the filled cop has been removed from the spindle of the machine and has been replaced by an empty sleeve, the thread of the fresh supply spool has been pulled directly downward through the traveler of the machine, set onto the ring and fastened to a suitable place on the spindle (generally, to the waste cone).

All the spindles of the machine have then been set rotating, for example, slowly at first, so as to allow insertion of the thread into the delivery mechanism of the machine. When this has been done, the thread has been applied over a first roll, and then over a second roll, as well as any third roll, if any, in the machines which have been used in the stretching of the thread. After the thread has been threaded in this way, the machine has usually been speeded up to normal production speed.

This above process, however, has the serious drawback that a relatively long time has been required for inserting the new thread. Thus, additional personnel which cannot be made use of otherwise in the production phase has been required. Moreover, the insertion of the new thread into the complete stretching mechanism, and all such mechanisms existing on the machine, takes considerable time, during which time material is being continuously wound on the waste cone. As a result, an undesirable amount of waste is accumulated.

In order to remedy this drawback, it has become known to insert threads in draw-twisting and draw-winding machines by cutting all the threads beyond the supply-spools, replacing the used supply-spools with fresh full spools, and by connecting the two thread ends of the old and new threads by a knot, so that .the thread continues to remain in the stretching mechanism and does not have to be fed in anew. However, because the connecting knots that have been made have the unpleasant characteristic of not permitting any great stretching of the thread without breakage of the thread, it has been proposed to reduce the stretching of the thread while the knot runs through the stretching mechanism. This can, on the one hand, be done by reducing the stretch ratio between the delivery mechanism and the first roll, either by raising the speed of delivery or by lowering the speed of the roll, or else, on the other hand, the same effect can be obtained by allowing the thread to slip in the delivery mechanism, through elimination of the clamp on the thread by simply lifting the pressureapplying roll. It would thus be possible to proceed in such a way that in the first stretching zone, where such a zone exists and which would in any event have a small stretch-ratio, things are left unaltered; while in the following second stretching zone, which effects a greater stretching, the stretch-ratio is reduced to about half, so that thread breakage can be avoided. It has also been known how to reduce the stretch-ratio by shifting the thread on the roll into a zone of lower friction so that slippage of the thread, and thus no stretching, occurs.

These latter described processes, however, also have serious drawbacks. For example, such cannot be carried out without additional expense in the form of drives and transmissions, couplings or clutches, devices for lifting the pressure-supplying delivery roll, gear arrangements, and special machining of roll surfaces.

It has also been proposed that the thread be drawn in by means of a loop-knot, so that no extra expense is required for the machine. This method is, however, disadvantageous, because a double thread runs from the tie point as far as the main stretching zone, wherein the knot is completely pulled together and, as a result, tangling can occur as early as the first roll. It has moreover proved to be extremely difficult to make the loop-knot of the correct length, because the space available is usually insufficient. Also, matching the loop-knot to the stretch-ratio is difficult and there is a great danger that the loop length may come out smaller than that required by the stretch-ratio. The knot can thus become drawn-up tight prematurely making a break of the thread in the high-stretch zone inevitable. Furthermore, monitoring the double thread during progress to the first roll is extremely difficult, because the knotting process has to be carried out in a space separate from and above the stretching zone.

Accordingly, it is an object of the invention to reduce the time required to replace used supply spools with fresh supply spools in draw-twisting and draw-winding machines.

It is another object of the invention to reduce the manpower required to replace supply spools in draw-twisting and draw-winding machines.

It is another object of the invention to reduce the quantity of waste in winding cops in draw-twisting and draw-winding machines.

It is another object of the invention to interrupt the normal operation of a draw-twisting or winding machine for a limited period of time for replacement of supply spools and wound cops.

Briefly, the invention provides a process of replacing exhausted supply spools and finish-spooled cops with fresh supply spools and sleeves in draw-twisting or draw-winding machines having stretching mechanisms therein within a stretching zone. The process is carried out generally in machines having a stretching mechanism which is supplied from a thread delivery mechanism and which includes a preliminary stretching zone in which a thread is stretched to a small degree and subsequent stretching zone in which the thread is stretched to relatively large degrees over a series of rollers.

The process is effected upon stopping of the machine while the not-normally stretched thread accumulates at a waste accumulation station and includes the steps of severing the thread between the supply spool and the delivery mechanism of the machine, removing the finish-wound cop and replacing of the used supply spool with a fresh supply spool, connecting the ends of the thread still in the stretching mechanism and the new thread together to form a connection, removing the thread from all the rollers following the preliminary stretching zone and pulling the thread to the waste accumulating station, installing a sleeve on the spindle, running the connection through the stretching zone at a slow rate until the connection reaches the waste accumulating station, and thereafter bringing the machine up to normal speed. In addition, as the machine returns to normal operating speed, the thread is wound onto the rollers of the stretching zone to permit stretching of the thread.

These and other objects and advantages of the invention will become more apparent from the following detailed description and appended claims taken in conjunction with the accompanying drawings in which:

FIG. 1 schematically illustrates the path of a thread in a draw-twisting machine up to the completion of a cop;

FIG. 2 schematically illustrates the path of the thread after removal of the cop;

FIG. 3 schematically illustrates the path of the thread after being removed from the rollers of the stretching zone; and

FIG. 4 schematically illustrates the path of the thread at the resumption of production speed.

Referring to FIG. 1, during normal operation, during production that is, a thread 1, which may be a monofilament or multifilament thread, runs in the draw-twist machine from a supply spool 2, which has already become very much emptied, by way of a thread-guide 3 and a deviating means 4 into a tube 6 set on a base 5. The base 5 serves to separate the separate spool-installation space 7 from the actual machine space 8 situated therebelow. After passing through the tube 6, the thread 1 reaches a delivery mechanism 9, and passes to and is wound around a first roller in a number of windings 1 1. The roller 10 has, for example, a peripheral speed that is at most 1.5 times the speed of the delivery mechanism 9 and subjects the thread 1 to a preliminary stretching in zone A. This zone A is followed by a main stretching zone B, provided with a heater 12. The thread 1 is guided through this zone B in contact with the heater 12 to become heated to a stretching temperature. 7

The stretching of the thread in zone Bis, for example, effected by being drawn along, about four times faster, by means of a roller 13 around which the thread 1 is wound in a number of windings 14. A further roller 15 takes over the thread, by means of a number of windings 16, in a third zone C at a somewhat lower peripheral speed, so that the thread 1 in zone C becomes correspondingly relaxed. Finally, the thread 1 passes through a thread-guide 17 onto a traveler l9 rotating on a ring 18, and passes to a sleeve 20, set removably on a spindle 21. By means of a suitable up and down movement of the ring 18, and rotation of the sleeve 20, the cop windings are put on as is known.

Instead of the described rotation-imparting ring-andtraveler combination (18, 19) the thread may be wound on a spool by means of a traverse-motion device, without imparting rotation as is known. In this case, it is a matter of a stretchingspooling process, as performed analogously in a stretchingspooling machine. It is self-evident that a machine as a rule has a plurality of stretching and wind-on organs arranged in rows for a correspondingly great number of threads, however only one station of the machine is illustrated for purposes of clarity.

When the build-up of the cop 22 is completed, then all the rings 18 are lowered to the level .of the waste-cone 23 on the respective spindles 21 under the cop 22. The machine is then brought to a stop in order to change the cop. If the supply of thread on the supply-spool 2 is no longer sufficient for building-up the next cop 22, then the supply-spool 2 must also be changed. This case, as a rule, occurs approximately at the same time for all the supply-spools.

Referring to H6. 2, initially all the threads between the supply-spools and the deviating means 4 are severed so that two thread-ends 24 and 24' are produced. The completed cops 22 are then taken off the spindles 21, and the waste is taken off the waste-cone 23 in the event that this cone has been filled to a great extent. The new full-up supply-spools 2 are now put on the machine (FIG. 3), after which the severed thread end 24 is, as by knotting together, connected with the 1 beginning 25 of the new supply-spool run through the threadguide 3. This connection 25' may be made in some other way, for example, through sticking or bonding the thread-ends together, or the equivalent.

In addition to the severing of the threads 1 upon stopping of the machine, the threads are also lifted away from theheater 12 into the pulled-out position shown in FIG. 1 by means of a thread lifter 26. ln this position, the thread is guided away from and below the heater 12.

Referring to FIG. 3, after the connection 25 is made the threads which are still pulled into the machine are, after going past the now-raised thread lifter 26, released by a removal of the windings l4, 16 from the rollers 13, 15 so that the thread 1 is now wrapped on only in the preliminary-stretching zone A. The thread 1 thus runs directly from the lifter 26 to the travler 19, and from there to the cone 23 on which the waste is accumulated. The length of thread liberated by the release of the windings l4, 16 is pulled onward, and is fastened anew in known manner to the waste cone 23. Next, the empty sleeves are set on the spindles 21. After the threads are all made ready in the described way in all locations of the machine, the machine is started up, at first in slow speed. While the machine is running slowly, the thread is wound on the wastecone 23 until the connection of each thread (the knot) has run down from the top of the machine upon or close to the waste-cone 23. Thereafter, the thread is laid on the still unoccupied rollers 13 and 15 by means of a number of windings 14 and 16 (FIG. 4). The machine is then speeded up to normal or production speed, and the thread is again applied to the heater 12, through a return movement of the thread-lifter 26.

Thus, normally stretched material is again supplied, and the ring 18 with the traveler 19 can begin the normal build-up of the cop.

While the machine is stopped, and before run through of the connection 25 at slow speed, the waste-cone can be freed of waste material.

The invention thus provides a process which has a number of substantial advantages. For example, the supplying-spools and the cops can be changed in a time-saving manner in that one man needs only about 5' to 10 seconds to reapply the thread on the rollers whereas with conventional methods the same work with three times the man-power can be done only in about 30 seconds. The process of the invention thus permits managing with less than half the previous personnel attending the machine. As a further and not inconslderable advantage,

' there is a greatly reduced quantity of waste, because the machine goes over to normal production within a very brief time, thus keeping waste to a minimum. A further advantage consists in that the thread-lifting at the heater can be introduced into the process without any complications at all. For example, this step can be carried out during the release of the windings from the rollers and also during the re-application of the thread upon these rollers. This is also advantageous in that unstretched material, such as occurs after putting the thread on the rollers, are not subjected to an unallowably high heating that would change the molecular structure, which would be manifested by extreme brittleness, and would inevitably lead to thread breakage.

What is claimed is: 1. A process of changing supply spools and finished wound cops in draw-twisting and draw-winding machines having a stretching mechanism including a preliminary stretching zone and subsequent stretching zones having rollers therein, a delivery mechanism for feeding thread to the stretching mechanism, and a waste accumulating station downstream of the stretching mechanism, said process including the steps of bringing the machine to a stop while winding thread at the waste accumulating station, severing the thread between the supply spool and delivery mechanism while retaining the thread in the stretching mechanism,

removing a finish wound cop from a spindle of the machine,

replacing the used supply spool with a fresh supply spool,

forming a connection between the severed thread and the beginning of the new thread from the fresh supply spool at a point between the delivery mechanism and the fresh supply spool,

removing the thread from the rollers in the subsequent stretching rollers and pulling the thread to the waste accumulating station for attachment thereat,

placing a sleeve on the spindle, and

running the machine at a low speed until the connection is wound up at the waste accumulating station and thereafter running the machine at production speed.

2. A process as set forth in claim 1 wherein the thread is wound onto the rollers of the subsequent stretching zones in a plurality of windings after the connection is formed and before running of the machine at production speed.

3. A process as set forth in claim 1 wherein the machine includes a heater for heating the thread in the subsequent stretching zone and which further includes the step of lifting the thread from the heater after serving of the thread and before running of the machine at low speed.

4. A process as set forth in claim 1 which further includes the step of freeing the waste accumulation station of waste material while the machine is stopped.

5. In a process of changing supply spools and finish wound cops in draw-twisting and draw-winding machines having a stretching mechanism defining a preliminary stretching zone and at least one subsequent stretching zone with rollers therein for winding of a thread thereon, the steps of forming a connection between the tail end of a thread havrunning the machine at a low speed until the connection is ing a Pomon located the Stretching Zones and wound up at the accumulation station and thereafter inthe begmmng end of a thread from a fresh pp y P L creasing the speed of the machine to production speed.

said tail end being located outside said stretching zones, removing the thread in the stretching mechanism from the rollers of the subsequent stretching zone, pulling the removed thread to a waste accumulation station outside the stretching mechanism, and I 6. In a process as set forth in claim 5 further including the step of winding the thread onto the rollers of the subsequent stretching zone after the machine reaches production speed. 

1. A process of changing supply spools and finished wound cops in draw-twisting and draw-winding machines having a stretching mechanism including a preliminary stretching zone and subsequent stretching zones having rollers therein, a delivery mechanism for feeding thread to the stRetching mechanism, and a waste accumulating station downstream of the stretching mechanism, said process including the steps of bringing the machine to a stop while winding thread at the waste accumulating station, severing the thread between the supply spool and delivery mechanism while retaining the thread in the stretching mechanism, removing a finish wound cop from a spindle of the machine, replacing the used supply spool with a fresh supply spool, forming a connection between the severed thread and the beginning of the new thread from the fresh supply spool at a point between the delivery mechanism and the fresh supply spool, removing the thread from the rollers in the subsequent stretching rollers and pulling the thread to the waste accumulating station for attachment thereat, placing a sleeve on the spindle, and running the machine at a low speed until the connection is wound up at the waste accumulating station and thereafter running the machine at production speed.
 2. A process as set forth in claim 1 wherein the thread is wound onto the rollers of the subsequent stretching zones in a plurality of windings after the connection is formed and before running of the machine at production speed.
 3. A process as set forth in claim 1 wherein the machine includes a heater for heating the thread in the subsequent stretching zone and which further includes the step of lifting the thread from the heater after serving of the thread and before running of the machine at low speed.
 4. A process as set forth in claim 1 which further includes the step of freeing the waste accumulation station of waste material while the machine is stopped.
 5. In a process of changing supply spools and finish wound cops in draw-twisting and draw-winding machines having a stretching mechanism defining a preliminary stretching zone and at least one subsequent stretching zone with rollers therein for winding of a thread thereon, the steps of forming a connection between the tail end of a thread having a forward portion located in the stretching zones and the beginning end of a thread from a fresh supply spool, said tail end being located outside said stretching zones, removing the thread in the stretching mechanism from the rollers of the subsequent stretching zone, pulling the removed thread to a waste accumulation station outside the stretching mechanism, and running the machine at a low speed until the connection is wound up at the accumulation station and thereafter increasing the speed of the machine to production speed.
 6. In a process as set forth in claim 5 further including the step of winding the thread onto the rollers of the subsequent stretching zone after the machine reaches production speed. 